Add the rt linux 4.1.3-rt3 as base
[kvmfornfv.git] / kernel / net / bluetooth / a2mp.c
diff --git a/kernel/net/bluetooth/a2mp.c b/kernel/net/bluetooth/a2mp.c
new file mode 100644 (file)
index 0000000..5a04eb1
--- /dev/null
@@ -0,0 +1,1025 @@
+/*
+   Copyright (c) 2010,2011 Code Aurora Forum.  All rights reserved.
+   Copyright (c) 2011,2012 Intel Corp.
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License version 2 and
+   only version 2 as published by the Free Software Foundation.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+*/
+
+#include <net/bluetooth/bluetooth.h>
+#include <net/bluetooth/hci_core.h>
+#include <net/bluetooth/l2cap.h>
+
+#include "a2mp.h"
+#include "amp.h"
+
+#define A2MP_FEAT_EXT  0x8000
+
+/* Global AMP Manager list */
+static LIST_HEAD(amp_mgr_list);
+static DEFINE_MUTEX(amp_mgr_list_lock);
+
+/* A2MP build & send command helper functions */
+static struct a2mp_cmd *__a2mp_build(u8 code, u8 ident, u16 len, void *data)
+{
+       struct a2mp_cmd *cmd;
+       int plen;
+
+       plen = sizeof(*cmd) + len;
+       cmd = kzalloc(plen, GFP_KERNEL);
+       if (!cmd)
+               return NULL;
+
+       cmd->code = code;
+       cmd->ident = ident;
+       cmd->len = cpu_to_le16(len);
+
+       memcpy(cmd->data, data, len);
+
+       return cmd;
+}
+
+static void a2mp_send(struct amp_mgr *mgr, u8 code, u8 ident, u16 len, void *data)
+{
+       struct l2cap_chan *chan = mgr->a2mp_chan;
+       struct a2mp_cmd *cmd;
+       u16 total_len = len + sizeof(*cmd);
+       struct kvec iv;
+       struct msghdr msg;
+
+       cmd = __a2mp_build(code, ident, len, data);
+       if (!cmd)
+               return;
+
+       iv.iov_base = cmd;
+       iv.iov_len = total_len;
+
+       memset(&msg, 0, sizeof(msg));
+
+       iov_iter_kvec(&msg.msg_iter, WRITE | ITER_KVEC, &iv, 1, total_len);
+
+       l2cap_chan_send(chan, &msg, total_len);
+
+       kfree(cmd);
+}
+
+static u8 __next_ident(struct amp_mgr *mgr)
+{
+       if (++mgr->ident == 0)
+               mgr->ident = 1;
+
+       return mgr->ident;
+}
+
+static struct amp_mgr *amp_mgr_lookup_by_state(u8 state)
+{
+       struct amp_mgr *mgr;
+
+       mutex_lock(&amp_mgr_list_lock);
+       list_for_each_entry(mgr, &amp_mgr_list, list) {
+               if (test_and_clear_bit(state, &mgr->state)) {
+                       amp_mgr_get(mgr);
+                       mutex_unlock(&amp_mgr_list_lock);
+                       return mgr;
+               }
+       }
+       mutex_unlock(&amp_mgr_list_lock);
+
+       return NULL;
+}
+
+/* hci_dev_list shall be locked */
+static void __a2mp_add_cl(struct amp_mgr *mgr, struct a2mp_cl *cl)
+{
+       struct hci_dev *hdev;
+       int i = 1;
+
+       cl[0].id = AMP_ID_BREDR;
+       cl[0].type = AMP_TYPE_BREDR;
+       cl[0].status = AMP_STATUS_BLUETOOTH_ONLY;
+
+       list_for_each_entry(hdev, &hci_dev_list, list) {
+               if (hdev->dev_type == HCI_AMP) {
+                       cl[i].id = hdev->id;
+                       cl[i].type = hdev->amp_type;
+                       if (test_bit(HCI_UP, &hdev->flags))
+                               cl[i].status = hdev->amp_status;
+                       else
+                               cl[i].status = AMP_STATUS_POWERED_DOWN;
+                       i++;
+               }
+       }
+}
+
+/* Processing A2MP messages */
+static int a2mp_command_rej(struct amp_mgr *mgr, struct sk_buff *skb,
+                           struct a2mp_cmd *hdr)
+{
+       struct a2mp_cmd_rej *rej = (void *) skb->data;
+
+       if (le16_to_cpu(hdr->len) < sizeof(*rej))
+               return -EINVAL;
+
+       BT_DBG("ident %d reason %d", hdr->ident, le16_to_cpu(rej->reason));
+
+       skb_pull(skb, sizeof(*rej));
+
+       return 0;
+}
+
+static int a2mp_discover_req(struct amp_mgr *mgr, struct sk_buff *skb,
+                            struct a2mp_cmd *hdr)
+{
+       struct a2mp_discov_req *req = (void *) skb->data;
+       u16 len = le16_to_cpu(hdr->len);
+       struct a2mp_discov_rsp *rsp;
+       u16 ext_feat;
+       u8 num_ctrl;
+       struct hci_dev *hdev;
+
+       if (len < sizeof(*req))
+               return -EINVAL;
+
+       skb_pull(skb, sizeof(*req));
+
+       ext_feat = le16_to_cpu(req->ext_feat);
+
+       BT_DBG("mtu %d efm 0x%4.4x", le16_to_cpu(req->mtu), ext_feat);
+
+       /* check that packet is not broken for now */
+       while (ext_feat & A2MP_FEAT_EXT) {
+               if (len < sizeof(ext_feat))
+                       return -EINVAL;
+
+               ext_feat = get_unaligned_le16(skb->data);
+               BT_DBG("efm 0x%4.4x", ext_feat);
+               len -= sizeof(ext_feat);
+               skb_pull(skb, sizeof(ext_feat));
+       }
+
+       read_lock(&hci_dev_list_lock);
+
+       /* at minimum the BR/EDR needs to be listed */
+       num_ctrl = 1;
+
+       list_for_each_entry(hdev, &hci_dev_list, list) {
+               if (hdev->dev_type == HCI_AMP)
+                       num_ctrl++;
+       }
+
+       len = num_ctrl * sizeof(struct a2mp_cl) + sizeof(*rsp);
+       rsp = kmalloc(len, GFP_ATOMIC);
+       if (!rsp) {
+               read_unlock(&hci_dev_list_lock);
+               return -ENOMEM;
+       }
+
+       rsp->mtu = cpu_to_le16(L2CAP_A2MP_DEFAULT_MTU);
+       rsp->ext_feat = 0;
+
+       __a2mp_add_cl(mgr, rsp->cl);
+
+       read_unlock(&hci_dev_list_lock);
+
+       a2mp_send(mgr, A2MP_DISCOVER_RSP, hdr->ident, len, rsp);
+
+       kfree(rsp);
+       return 0;
+}
+
+static int a2mp_discover_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
+                            struct a2mp_cmd *hdr)
+{
+       struct a2mp_discov_rsp *rsp = (void *) skb->data;
+       u16 len = le16_to_cpu(hdr->len);
+       struct a2mp_cl *cl;
+       u16 ext_feat;
+       bool found = false;
+
+       if (len < sizeof(*rsp))
+               return -EINVAL;
+
+       len -= sizeof(*rsp);
+       skb_pull(skb, sizeof(*rsp));
+
+       ext_feat = le16_to_cpu(rsp->ext_feat);
+
+       BT_DBG("mtu %d efm 0x%4.4x", le16_to_cpu(rsp->mtu), ext_feat);
+
+       /* check that packet is not broken for now */
+       while (ext_feat & A2MP_FEAT_EXT) {
+               if (len < sizeof(ext_feat))
+                       return -EINVAL;
+
+               ext_feat = get_unaligned_le16(skb->data);
+               BT_DBG("efm 0x%4.4x", ext_feat);
+               len -= sizeof(ext_feat);
+               skb_pull(skb, sizeof(ext_feat));
+       }
+
+       cl = (void *) skb->data;
+       while (len >= sizeof(*cl)) {
+               BT_DBG("Remote AMP id %d type %d status %d", cl->id, cl->type,
+                      cl->status);
+
+               if (cl->id != AMP_ID_BREDR && cl->type != AMP_TYPE_BREDR) {
+                       struct a2mp_info_req req;
+
+                       found = true;
+                       req.id = cl->id;
+                       a2mp_send(mgr, A2MP_GETINFO_REQ, __next_ident(mgr),
+                                 sizeof(req), &req);
+               }
+
+               len -= sizeof(*cl);
+               cl = (void *) skb_pull(skb, sizeof(*cl));
+       }
+
+       /* Fall back to L2CAP init sequence */
+       if (!found) {
+               struct l2cap_conn *conn = mgr->l2cap_conn;
+               struct l2cap_chan *chan;
+
+               mutex_lock(&conn->chan_lock);
+
+               list_for_each_entry(chan, &conn->chan_l, list) {
+
+                       BT_DBG("chan %p state %s", chan,
+                              state_to_string(chan->state));
+
+                       if (chan->scid == L2CAP_CID_A2MP)
+                               continue;
+
+                       l2cap_chan_lock(chan);
+
+                       if (chan->state == BT_CONNECT)
+                               l2cap_send_conn_req(chan);
+
+                       l2cap_chan_unlock(chan);
+               }
+
+               mutex_unlock(&conn->chan_lock);
+       }
+
+       return 0;
+}
+
+static int a2mp_change_notify(struct amp_mgr *mgr, struct sk_buff *skb,
+                             struct a2mp_cmd *hdr)
+{
+       struct a2mp_cl *cl = (void *) skb->data;
+
+       while (skb->len >= sizeof(*cl)) {
+               BT_DBG("Controller id %d type %d status %d", cl->id, cl->type,
+                      cl->status);
+               cl = (struct a2mp_cl *) skb_pull(skb, sizeof(*cl));
+       }
+
+       /* TODO send A2MP_CHANGE_RSP */
+
+       return 0;
+}
+
+static int a2mp_getinfo_req(struct amp_mgr *mgr, struct sk_buff *skb,
+                           struct a2mp_cmd *hdr)
+{
+       struct a2mp_info_req *req  = (void *) skb->data;
+       struct hci_dev *hdev;
+
+       if (le16_to_cpu(hdr->len) < sizeof(*req))
+               return -EINVAL;
+
+       BT_DBG("id %d", req->id);
+
+       hdev = hci_dev_get(req->id);
+       if (!hdev || hdev->dev_type != HCI_AMP) {
+               struct a2mp_info_rsp rsp;
+
+               rsp.id = req->id;
+               rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
+
+               a2mp_send(mgr, A2MP_GETINFO_RSP, hdr->ident, sizeof(rsp),
+                         &rsp);
+
+               goto done;
+       }
+
+       set_bit(READ_LOC_AMP_INFO, &mgr->state);
+       hci_send_cmd(hdev, HCI_OP_READ_LOCAL_AMP_INFO, 0, NULL);
+
+done:
+       if (hdev)
+               hci_dev_put(hdev);
+
+       skb_pull(skb, sizeof(*req));
+       return 0;
+}
+
+static int a2mp_getinfo_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
+                           struct a2mp_cmd *hdr)
+{
+       struct a2mp_info_rsp *rsp = (struct a2mp_info_rsp *) skb->data;
+       struct a2mp_amp_assoc_req req;
+       struct amp_ctrl *ctrl;
+
+       if (le16_to_cpu(hdr->len) < sizeof(*rsp))
+               return -EINVAL;
+
+       BT_DBG("id %d status 0x%2.2x", rsp->id, rsp->status);
+
+       if (rsp->status)
+               return -EINVAL;
+
+       ctrl = amp_ctrl_add(mgr, rsp->id);
+       if (!ctrl)
+               return -ENOMEM;
+
+       req.id = rsp->id;
+       a2mp_send(mgr, A2MP_GETAMPASSOC_REQ, __next_ident(mgr), sizeof(req),
+                 &req);
+
+       skb_pull(skb, sizeof(*rsp));
+       return 0;
+}
+
+static int a2mp_getampassoc_req(struct amp_mgr *mgr, struct sk_buff *skb,
+                               struct a2mp_cmd *hdr)
+{
+       struct a2mp_amp_assoc_req *req = (void *) skb->data;
+       struct hci_dev *hdev;
+       struct amp_mgr *tmp;
+
+       if (le16_to_cpu(hdr->len) < sizeof(*req))
+               return -EINVAL;
+
+       BT_DBG("id %d", req->id);
+
+       /* Make sure that other request is not processed */
+       tmp = amp_mgr_lookup_by_state(READ_LOC_AMP_ASSOC);
+
+       hdev = hci_dev_get(req->id);
+       if (!hdev || hdev->amp_type == AMP_TYPE_BREDR || tmp) {
+               struct a2mp_amp_assoc_rsp rsp;
+               rsp.id = req->id;
+
+               if (tmp) {
+                       rsp.status = A2MP_STATUS_COLLISION_OCCURED;
+                       amp_mgr_put(tmp);
+               } else {
+                       rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
+               }
+
+               a2mp_send(mgr, A2MP_GETAMPASSOC_RSP, hdr->ident, sizeof(rsp),
+                         &rsp);
+
+               goto done;
+       }
+
+       amp_read_loc_assoc(hdev, mgr);
+
+done:
+       if (hdev)
+               hci_dev_put(hdev);
+
+       skb_pull(skb, sizeof(*req));
+       return 0;
+}
+
+static int a2mp_getampassoc_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
+                               struct a2mp_cmd *hdr)
+{
+       struct a2mp_amp_assoc_rsp *rsp = (void *) skb->data;
+       u16 len = le16_to_cpu(hdr->len);
+       struct hci_dev *hdev;
+       struct amp_ctrl *ctrl;
+       struct hci_conn *hcon;
+       size_t assoc_len;
+
+       if (len < sizeof(*rsp))
+               return -EINVAL;
+
+       assoc_len = len - sizeof(*rsp);
+
+       BT_DBG("id %d status 0x%2.2x assoc len %zu", rsp->id, rsp->status,
+              assoc_len);
+
+       if (rsp->status)
+               return -EINVAL;
+
+       /* Save remote ASSOC data */
+       ctrl = amp_ctrl_lookup(mgr, rsp->id);
+       if (ctrl) {
+               u8 *assoc;
+
+               assoc = kmemdup(rsp->amp_assoc, assoc_len, GFP_KERNEL);
+               if (!assoc) {
+                       amp_ctrl_put(ctrl);
+                       return -ENOMEM;
+               }
+
+               ctrl->assoc = assoc;
+               ctrl->assoc_len = assoc_len;
+               ctrl->assoc_rem_len = assoc_len;
+               ctrl->assoc_len_so_far = 0;
+
+               amp_ctrl_put(ctrl);
+       }
+
+       /* Create Phys Link */
+       hdev = hci_dev_get(rsp->id);
+       if (!hdev)
+               return -EINVAL;
+
+       hcon = phylink_add(hdev, mgr, rsp->id, true);
+       if (!hcon)
+               goto done;
+
+       BT_DBG("Created hcon %p: loc:%d -> rem:%d", hcon, hdev->id, rsp->id);
+
+       mgr->bredr_chan->remote_amp_id = rsp->id;
+
+       amp_create_phylink(hdev, mgr, hcon);
+
+done:
+       hci_dev_put(hdev);
+       skb_pull(skb, len);
+       return 0;
+}
+
+static int a2mp_createphyslink_req(struct amp_mgr *mgr, struct sk_buff *skb,
+                                  struct a2mp_cmd *hdr)
+{
+       struct a2mp_physlink_req *req = (void *) skb->data;
+
+       struct a2mp_physlink_rsp rsp;
+       struct hci_dev *hdev;
+       struct hci_conn *hcon;
+       struct amp_ctrl *ctrl;
+
+       if (le16_to_cpu(hdr->len) < sizeof(*req))
+               return -EINVAL;
+
+       BT_DBG("local_id %d, remote_id %d", req->local_id, req->remote_id);
+
+       rsp.local_id = req->remote_id;
+       rsp.remote_id = req->local_id;
+
+       hdev = hci_dev_get(req->remote_id);
+       if (!hdev || hdev->amp_type == AMP_TYPE_BREDR) {
+               rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
+               goto send_rsp;
+       }
+
+       ctrl = amp_ctrl_lookup(mgr, rsp.remote_id);
+       if (!ctrl) {
+               ctrl = amp_ctrl_add(mgr, rsp.remote_id);
+               if (ctrl) {
+                       amp_ctrl_get(ctrl);
+               } else {
+                       rsp.status = A2MP_STATUS_UNABLE_START_LINK_CREATION;
+                       goto send_rsp;
+               }
+       }
+
+       if (ctrl) {
+               size_t assoc_len = le16_to_cpu(hdr->len) - sizeof(*req);
+               u8 *assoc;
+
+               assoc = kmemdup(req->amp_assoc, assoc_len, GFP_KERNEL);
+               if (!assoc) {
+                       amp_ctrl_put(ctrl);
+                       return -ENOMEM;
+               }
+
+               ctrl->assoc = assoc;
+               ctrl->assoc_len = assoc_len;
+               ctrl->assoc_rem_len = assoc_len;
+               ctrl->assoc_len_so_far = 0;
+
+               amp_ctrl_put(ctrl);
+       }
+
+       hcon = phylink_add(hdev, mgr, req->local_id, false);
+       if (hcon) {
+               amp_accept_phylink(hdev, mgr, hcon);
+               rsp.status = A2MP_STATUS_SUCCESS;
+       } else {
+               rsp.status = A2MP_STATUS_UNABLE_START_LINK_CREATION;
+       }
+
+send_rsp:
+       if (hdev)
+               hci_dev_put(hdev);
+
+       /* Reply error now and success after HCI Write Remote AMP Assoc
+          command complete with success status
+        */
+       if (rsp.status != A2MP_STATUS_SUCCESS) {
+               a2mp_send(mgr, A2MP_CREATEPHYSLINK_RSP, hdr->ident,
+                         sizeof(rsp), &rsp);
+       } else {
+               set_bit(WRITE_REMOTE_AMP_ASSOC, &mgr->state);
+               mgr->ident = hdr->ident;
+       }
+
+       skb_pull(skb, le16_to_cpu(hdr->len));
+       return 0;
+}
+
+static int a2mp_discphyslink_req(struct amp_mgr *mgr, struct sk_buff *skb,
+                                struct a2mp_cmd *hdr)
+{
+       struct a2mp_physlink_req *req = (void *) skb->data;
+       struct a2mp_physlink_rsp rsp;
+       struct hci_dev *hdev;
+       struct hci_conn *hcon;
+
+       if (le16_to_cpu(hdr->len) < sizeof(*req))
+               return -EINVAL;
+
+       BT_DBG("local_id %d remote_id %d", req->local_id, req->remote_id);
+
+       rsp.local_id = req->remote_id;
+       rsp.remote_id = req->local_id;
+       rsp.status = A2MP_STATUS_SUCCESS;
+
+       hdev = hci_dev_get(req->remote_id);
+       if (!hdev) {
+               rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
+               goto send_rsp;
+       }
+
+       hcon = hci_conn_hash_lookup_ba(hdev, AMP_LINK,
+                                      &mgr->l2cap_conn->hcon->dst);
+       if (!hcon) {
+               BT_ERR("No phys link exist");
+               rsp.status = A2MP_STATUS_NO_PHYSICAL_LINK_EXISTS;
+               goto clean;
+       }
+
+       /* TODO Disconnect Phys Link here */
+
+clean:
+       hci_dev_put(hdev);
+
+send_rsp:
+       a2mp_send(mgr, A2MP_DISCONNPHYSLINK_RSP, hdr->ident, sizeof(rsp), &rsp);
+
+       skb_pull(skb, sizeof(*req));
+       return 0;
+}
+
+static inline int a2mp_cmd_rsp(struct amp_mgr *mgr, struct sk_buff *skb,
+                              struct a2mp_cmd *hdr)
+{
+       BT_DBG("ident %d code 0x%2.2x", hdr->ident, hdr->code);
+
+       skb_pull(skb, le16_to_cpu(hdr->len));
+       return 0;
+}
+
+/* Handle A2MP signalling */
+static int a2mp_chan_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
+{
+       struct a2mp_cmd *hdr;
+       struct amp_mgr *mgr = chan->data;
+       int err = 0;
+
+       amp_mgr_get(mgr);
+
+       while (skb->len >= sizeof(*hdr)) {
+               u16 len;
+
+               hdr = (void *) skb->data;
+               len = le16_to_cpu(hdr->len);
+
+               BT_DBG("code 0x%2.2x id %d len %u", hdr->code, hdr->ident, len);
+
+               skb_pull(skb, sizeof(*hdr));
+
+               if (len > skb->len || !hdr->ident) {
+                       err = -EINVAL;
+                       break;
+               }
+
+               mgr->ident = hdr->ident;
+
+               switch (hdr->code) {
+               case A2MP_COMMAND_REJ:
+                       a2mp_command_rej(mgr, skb, hdr);
+                       break;
+
+               case A2MP_DISCOVER_REQ:
+                       err = a2mp_discover_req(mgr, skb, hdr);
+                       break;
+
+               case A2MP_CHANGE_NOTIFY:
+                       err = a2mp_change_notify(mgr, skb, hdr);
+                       break;
+
+               case A2MP_GETINFO_REQ:
+                       err = a2mp_getinfo_req(mgr, skb, hdr);
+                       break;
+
+               case A2MP_GETAMPASSOC_REQ:
+                       err = a2mp_getampassoc_req(mgr, skb, hdr);
+                       break;
+
+               case A2MP_CREATEPHYSLINK_REQ:
+                       err = a2mp_createphyslink_req(mgr, skb, hdr);
+                       break;
+
+               case A2MP_DISCONNPHYSLINK_REQ:
+                       err = a2mp_discphyslink_req(mgr, skb, hdr);
+                       break;
+
+               case A2MP_DISCOVER_RSP:
+                       err = a2mp_discover_rsp(mgr, skb, hdr);
+                       break;
+
+               case A2MP_GETINFO_RSP:
+                       err = a2mp_getinfo_rsp(mgr, skb, hdr);
+                       break;
+
+               case A2MP_GETAMPASSOC_RSP:
+                       err = a2mp_getampassoc_rsp(mgr, skb, hdr);
+                       break;
+
+               case A2MP_CHANGE_RSP:
+               case A2MP_CREATEPHYSLINK_RSP:
+               case A2MP_DISCONNPHYSLINK_RSP:
+                       err = a2mp_cmd_rsp(mgr, skb, hdr);
+                       break;
+
+               default:
+                       BT_ERR("Unknown A2MP sig cmd 0x%2.2x", hdr->code);
+                       err = -EINVAL;
+                       break;
+               }
+       }
+
+       if (err) {
+               struct a2mp_cmd_rej rej;
+
+               rej.reason = cpu_to_le16(0);
+               hdr = (void *) skb->data;
+
+               BT_DBG("Send A2MP Rej: cmd 0x%2.2x err %d", hdr->code, err);
+
+               a2mp_send(mgr, A2MP_COMMAND_REJ, hdr->ident, sizeof(rej),
+                         &rej);
+       }
+
+       /* Always free skb and return success error code to prevent
+          from sending L2CAP Disconnect over A2MP channel */
+       kfree_skb(skb);
+
+       amp_mgr_put(mgr);
+
+       return 0;
+}
+
+static void a2mp_chan_close_cb(struct l2cap_chan *chan)
+{
+       l2cap_chan_put(chan);
+}
+
+static void a2mp_chan_state_change_cb(struct l2cap_chan *chan, int state,
+                                     int err)
+{
+       struct amp_mgr *mgr = chan->data;
+
+       if (!mgr)
+               return;
+
+       BT_DBG("chan %p state %s", chan, state_to_string(state));
+
+       chan->state = state;
+
+       switch (state) {
+       case BT_CLOSED:
+               if (mgr)
+                       amp_mgr_put(mgr);
+               break;
+       }
+}
+
+static struct sk_buff *a2mp_chan_alloc_skb_cb(struct l2cap_chan *chan,
+                                             unsigned long hdr_len,
+                                             unsigned long len, int nb)
+{
+       struct sk_buff *skb;
+
+       skb = bt_skb_alloc(hdr_len + len, GFP_KERNEL);
+       if (!skb)
+               return ERR_PTR(-ENOMEM);
+
+       return skb;
+}
+
+static const struct l2cap_ops a2mp_chan_ops = {
+       .name = "L2CAP A2MP channel",
+       .recv = a2mp_chan_recv_cb,
+       .close = a2mp_chan_close_cb,
+       .state_change = a2mp_chan_state_change_cb,
+       .alloc_skb = a2mp_chan_alloc_skb_cb,
+
+       /* Not implemented for A2MP */
+       .new_connection = l2cap_chan_no_new_connection,
+       .teardown = l2cap_chan_no_teardown,
+       .ready = l2cap_chan_no_ready,
+       .defer = l2cap_chan_no_defer,
+       .resume = l2cap_chan_no_resume,
+       .set_shutdown = l2cap_chan_no_set_shutdown,
+       .get_sndtimeo = l2cap_chan_no_get_sndtimeo,
+};
+
+static struct l2cap_chan *a2mp_chan_open(struct l2cap_conn *conn, bool locked)
+{
+       struct l2cap_chan *chan;
+       int err;
+
+       chan = l2cap_chan_create();
+       if (!chan)
+               return NULL;
+
+       BT_DBG("chan %p", chan);
+
+       chan->chan_type = L2CAP_CHAN_FIXED;
+       chan->scid = L2CAP_CID_A2MP;
+       chan->dcid = L2CAP_CID_A2MP;
+       chan->omtu = L2CAP_A2MP_DEFAULT_MTU;
+       chan->imtu = L2CAP_A2MP_DEFAULT_MTU;
+       chan->flush_to = L2CAP_DEFAULT_FLUSH_TO;
+
+       chan->ops = &a2mp_chan_ops;
+
+       l2cap_chan_set_defaults(chan);
+       chan->remote_max_tx = chan->max_tx;
+       chan->remote_tx_win = chan->tx_win;
+
+       chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
+       chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
+
+       skb_queue_head_init(&chan->tx_q);
+
+       chan->mode = L2CAP_MODE_ERTM;
+
+       err = l2cap_ertm_init(chan);
+       if (err < 0) {
+               l2cap_chan_del(chan, 0);
+               return NULL;
+       }
+
+       chan->conf_state = 0;
+
+       if (locked)
+               __l2cap_chan_add(conn, chan);
+       else
+               l2cap_chan_add(conn, chan);
+
+       chan->remote_mps = chan->omtu;
+       chan->mps = chan->omtu;
+
+       chan->state = BT_CONNECTED;
+
+       return chan;
+}
+
+/* AMP Manager functions */
+struct amp_mgr *amp_mgr_get(struct amp_mgr *mgr)
+{
+       BT_DBG("mgr %p orig refcnt %d", mgr, atomic_read(&mgr->kref.refcount));
+
+       kref_get(&mgr->kref);
+
+       return mgr;
+}
+
+static void amp_mgr_destroy(struct kref *kref)
+{
+       struct amp_mgr *mgr = container_of(kref, struct amp_mgr, kref);
+
+       BT_DBG("mgr %p", mgr);
+
+       mutex_lock(&amp_mgr_list_lock);
+       list_del(&mgr->list);
+       mutex_unlock(&amp_mgr_list_lock);
+
+       amp_ctrl_list_flush(mgr);
+       kfree(mgr);
+}
+
+int amp_mgr_put(struct amp_mgr *mgr)
+{
+       BT_DBG("mgr %p orig refcnt %d", mgr, atomic_read(&mgr->kref.refcount));
+
+       return kref_put(&mgr->kref, &amp_mgr_destroy);
+}
+
+static struct amp_mgr *amp_mgr_create(struct l2cap_conn *conn, bool locked)
+{
+       struct amp_mgr *mgr;
+       struct l2cap_chan *chan;
+
+       mgr = kzalloc(sizeof(*mgr), GFP_KERNEL);
+       if (!mgr)
+               return NULL;
+
+       BT_DBG("conn %p mgr %p", conn, mgr);
+
+       mgr->l2cap_conn = conn;
+
+       chan = a2mp_chan_open(conn, locked);
+       if (!chan) {
+               kfree(mgr);
+               return NULL;
+       }
+
+       mgr->a2mp_chan = chan;
+       chan->data = mgr;
+
+       conn->hcon->amp_mgr = mgr;
+
+       kref_init(&mgr->kref);
+
+       /* Remote AMP ctrl list initialization */
+       INIT_LIST_HEAD(&mgr->amp_ctrls);
+       mutex_init(&mgr->amp_ctrls_lock);
+
+       mutex_lock(&amp_mgr_list_lock);
+       list_add(&mgr->list, &amp_mgr_list);
+       mutex_unlock(&amp_mgr_list_lock);
+
+       return mgr;
+}
+
+struct l2cap_chan *a2mp_channel_create(struct l2cap_conn *conn,
+                                      struct sk_buff *skb)
+{
+       struct amp_mgr *mgr;
+
+       if (conn->hcon->type != ACL_LINK)
+               return NULL;
+
+       mgr = amp_mgr_create(conn, false);
+       if (!mgr) {
+               BT_ERR("Could not create AMP manager");
+               return NULL;
+       }
+
+       BT_DBG("mgr: %p chan %p", mgr, mgr->a2mp_chan);
+
+       return mgr->a2mp_chan;
+}
+
+void a2mp_send_getinfo_rsp(struct hci_dev *hdev)
+{
+       struct amp_mgr *mgr;
+       struct a2mp_info_rsp rsp;
+
+       mgr = amp_mgr_lookup_by_state(READ_LOC_AMP_INFO);
+       if (!mgr)
+               return;
+
+       BT_DBG("%s mgr %p", hdev->name, mgr);
+
+       rsp.id = hdev->id;
+       rsp.status = A2MP_STATUS_INVALID_CTRL_ID;
+
+       if (hdev->amp_type != AMP_TYPE_BREDR) {
+               rsp.status = 0;
+               rsp.total_bw = cpu_to_le32(hdev->amp_total_bw);
+               rsp.max_bw = cpu_to_le32(hdev->amp_max_bw);
+               rsp.min_latency = cpu_to_le32(hdev->amp_min_latency);
+               rsp.pal_cap = cpu_to_le16(hdev->amp_pal_cap);
+               rsp.assoc_size = cpu_to_le16(hdev->amp_assoc_size);
+       }
+
+       a2mp_send(mgr, A2MP_GETINFO_RSP, mgr->ident, sizeof(rsp), &rsp);
+       amp_mgr_put(mgr);
+}
+
+void a2mp_send_getampassoc_rsp(struct hci_dev *hdev, u8 status)
+{
+       struct amp_mgr *mgr;
+       struct amp_assoc *loc_assoc = &hdev->loc_assoc;
+       struct a2mp_amp_assoc_rsp *rsp;
+       size_t len;
+
+       mgr = amp_mgr_lookup_by_state(READ_LOC_AMP_ASSOC);
+       if (!mgr)
+               return;
+
+       BT_DBG("%s mgr %p", hdev->name, mgr);
+
+       len = sizeof(struct a2mp_amp_assoc_rsp) + loc_assoc->len;
+       rsp = kzalloc(len, GFP_KERNEL);
+       if (!rsp) {
+               amp_mgr_put(mgr);
+               return;
+       }
+
+       rsp->id = hdev->id;
+
+       if (status) {
+               rsp->status = A2MP_STATUS_INVALID_CTRL_ID;
+       } else {
+               rsp->status = A2MP_STATUS_SUCCESS;
+               memcpy(rsp->amp_assoc, loc_assoc->data, loc_assoc->len);
+       }
+
+       a2mp_send(mgr, A2MP_GETAMPASSOC_RSP, mgr->ident, len, rsp);
+       amp_mgr_put(mgr);
+       kfree(rsp);
+}
+
+void a2mp_send_create_phy_link_req(struct hci_dev *hdev, u8 status)
+{
+       struct amp_mgr *mgr;
+       struct amp_assoc *loc_assoc = &hdev->loc_assoc;
+       struct a2mp_physlink_req *req;
+       struct l2cap_chan *bredr_chan;
+       size_t len;
+
+       mgr = amp_mgr_lookup_by_state(READ_LOC_AMP_ASSOC_FINAL);
+       if (!mgr)
+               return;
+
+       len = sizeof(*req) + loc_assoc->len;
+
+       BT_DBG("%s mgr %p assoc_len %zu", hdev->name, mgr, len);
+
+       req = kzalloc(len, GFP_KERNEL);
+       if (!req) {
+               amp_mgr_put(mgr);
+               return;
+       }
+
+       bredr_chan = mgr->bredr_chan;
+       if (!bredr_chan)
+               goto clean;
+
+       req->local_id = hdev->id;
+       req->remote_id = bredr_chan->remote_amp_id;
+       memcpy(req->amp_assoc, loc_assoc->data, loc_assoc->len);
+
+       a2mp_send(mgr, A2MP_CREATEPHYSLINK_REQ, __next_ident(mgr), len, req);
+
+clean:
+       amp_mgr_put(mgr);
+       kfree(req);
+}
+
+void a2mp_send_create_phy_link_rsp(struct hci_dev *hdev, u8 status)
+{
+       struct amp_mgr *mgr;
+       struct a2mp_physlink_rsp rsp;
+       struct hci_conn *hs_hcon;
+
+       mgr = amp_mgr_lookup_by_state(WRITE_REMOTE_AMP_ASSOC);
+       if (!mgr)
+               return;
+
+       hs_hcon = hci_conn_hash_lookup_state(hdev, AMP_LINK, BT_CONNECT);
+       if (!hs_hcon) {
+               rsp.status = A2MP_STATUS_UNABLE_START_LINK_CREATION;
+       } else {
+               rsp.remote_id = hs_hcon->remote_id;
+               rsp.status = A2MP_STATUS_SUCCESS;
+       }
+
+       BT_DBG("%s mgr %p hs_hcon %p status %u", hdev->name, mgr, hs_hcon,
+              status);
+
+       rsp.local_id = hdev->id;
+       a2mp_send(mgr, A2MP_CREATEPHYSLINK_RSP, mgr->ident, sizeof(rsp), &rsp);
+       amp_mgr_put(mgr);
+}
+
+void a2mp_discover_amp(struct l2cap_chan *chan)
+{
+       struct l2cap_conn *conn = chan->conn;
+       struct amp_mgr *mgr = conn->hcon->amp_mgr;
+       struct a2mp_discov_req req;
+
+       BT_DBG("chan %p conn %p mgr %p", chan, conn, mgr);
+
+       if (!mgr) {
+               mgr = amp_mgr_create(conn, true);
+               if (!mgr)
+                       return;
+       }
+
+       mgr->bredr_chan = chan;
+
+       req.mtu = cpu_to_le16(L2CAP_A2MP_DEFAULT_MTU);
+       req.ext_feat = 0;
+       a2mp_send(mgr, A2MP_DISCOVER_REQ, 1, sizeof(req), &req);
+}